﻿using FaceppSDK;
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.IO;
using System.Net;

namespace Wechat.Util.Image
{
    public class ImageUtil
    {

        #region 保存web图片到本地

        /// <summary>
        /// 保存web图片到本地
        /// </summary>
        /// <param name="imgUrl">web图片路径</param>
        /// <param name="path">保存路径</param>
        /// <param name="fileName">保存文件名</param>
        /// <returns></returns>
        public static string SaveImageFromWeb(string imgUrl, string path, string fileName)
        {
            string imgPath = "";
            if (path.Equals(""))
                throw new Exception("未指定保存文件的路径");
            string imgName = imgUrl.ToString().Substring(imgUrl.ToString().LastIndexOf("/") + 1);
            string defaultType = ".jpg";
            string[] imgTypes = new string[] { ".jpg", ".jpeg", ".png", ".gif", ".bmp" };
            string imgType = imgUrl.ToString().Substring(imgUrl.ToString().LastIndexOf("."));

            foreach (string it in imgTypes)
            {
                if (imgType.ToLower().Equals(it))
                    break;
                if (it.Equals(".bmp"))
                    imgType = defaultType;
            }

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(imgUrl);
            request.UserAgent = "Mozilla/6.0 (MSIE 6.0; Windows NT 5.1; Natas.Robot)";
            request.Timeout = 3000;

            WebResponse response = request.GetResponse();
            Stream stream = response.GetResponseStream();

            if (response.ContentType.ToLower().StartsWith("image/"))
            {
                byte[] arrayByte = new byte[1024];
                int imgLong = (int)response.ContentLength;
                int l = 0;

                if (fileName == "")
                    fileName = imgName;

                FileStream fso = new FileStream(path + fileName + imgType, FileMode.Create);
                while (l < imgLong)
                {
                    int i = stream.Read(arrayByte, 0, 1024);
                    fso.Write(arrayByte, 0, i);
                    l += i;
                }

                fso.Close();
                stream.Close();
                response.Close();
                imgPath = fileName + imgType;
            }
            else
            {
                imgPath = "";
            }
            return imgPath;
        }
        #endregion

        #region 对图片进行处理
        /// <summary>
        /// 在图片上画框
        /// </summary>
        /// <param name="bmp">原始图</param>
        /// <param name="p0">起始点</param>
        /// <param name="p1">终止点</param>
        /// <param name="RectColor">矩形框颜色</param>
        /// <param name="LineWidth">矩形框边界</param>
        /// <returns></returns>
        public static Bitmap DrawRectangleInPicture(Bitmap bmp, DetectResult res, Color RectColor, int LineWidth, DashStyle ds)
        {
            if (bmp == null) return null;
            Graphics g = Graphics.FromImage(bmp);

            Brush brush = new SolidBrush(RectColor);
            Pen pen = new Pen(brush, LineWidth);
            pen.DashStyle = ds;
            for (int i = 0; i < res.face.Count; ++i)
            {
                g.DrawRectangle(pen, new Rectangle(max(res.face[i].center.x * bmp.Width / 100.0 - res.face[i].width * bmp.Width / 200.0, 0),
                                      max(res.face[i].center.y * bmp.Height / 100.0 - res.face[i].height * bmp.Height / 200.0, 0),
                                     Convert.ToInt32(res.face[i].width * bmp.Width / 100.0), Convert.ToInt32(res.face[i].height * bmp.Height / 100.0)));
            }
            g.Dispose();

            return bmp;
        }
        private static int max(double x, double y)
        {
            return (x > y) ? Convert.ToInt32(x) : Convert.ToInt32(y);
        }
        #endregion
    }
}
